Blood Transfusion Study: Cord Blood Better than Bone Marrow

Researchers report the rate of rejection, infection and hospitalization are lower among leukemia patients receiving cord blood than those receiving matched, unrelated bone marrow. The study's results may lead doctors to lean towards cord blood as a transplant option over bone marrow when deciding what’s best for their patients.

A common treatment for blood cancers such as leukemia is to, over time, wipe the cancerous blood system and replace it with new, clean blood cells. Cord blood and bone marrow stem cells are administered to effectively replace the old blood.

The study

The study published in the journal Bone Marrow Transplantation[i] and conducted at the University of Colorado compared 51 patients receiving cord blood transplants with 57 patients receiving marrow from a matched, unrelated donor. Cord blood yielded significantly better results in every area under consideration:

At 3 years post-transplant, the incidence of graft-versus-host disease (GVHD), which occurs when the new blood cells attack the patient, was 48% among the patients who had received marrow from a matched, unrelated donor and 8% among patients who had received cord blood transplants.

At 3 years post-transplant, patients who had received cord blood transplants were off immunosuppressant drugs by a median of 268 days from transplant while patients who had received marrow from a matched, unrelated donor had not been taken off the drugs.

“It takes cord blood cells a little longer to get going and so patients need to be supported a little longer,” explains Dr. Jonathan Gutman, investigator at the CU Cancer Center and Clinical Director of Allogeneic Stem Cell Transplantation at University of Colorado Hospital. “However, when you look past the first 100 days—a point at which many centers stop collecting data—there is clear evidence that cord blood outperforms cells from matched, unrelated donors."

Risk of graft-versus-host

The closer the match between patient and donor, the less likely the patient will suffer from GVHD, which can be debilitating and, in some instances, fatal.

"Our results show that, long term, receiving a cord blood transplant is less likely than receiving a transplant from an unrelated, matched donor to result in graft-versus-host disease," explains Dr. Gutman.

What makes cord blood better?

Using umbilical cord blood—immature stem cells—is better because it does not need to be as closely matched to a patient to be considered acceptable as a donor source. In other words, these stem cells have a greater propensity for acceptance by the patient’s immune system.

"As a result, we have chosen to use cord blood as our first choice in cases where a matched, related donor is unavailable," Gutman says.